1. Field of the Invention
The present invention relates to a cleaning vehicle for cleaning a rail, for example, for a conveying vehicle to travel installed in a clean room.
2. Description of the Related Art
In places, such as a hospital, required to keep a clean air at a high degree (cleanliness degree), conveying vehicles are used for automatically conveying articles. As such conveying vehicles, there is an overhead traveling type having an advantage of not interfering with other operations (for example, refer to the patent article 1: The Japanese Patent Publication No. 11-100120).
Such an overhead traveling type conveying vehicle is configured that a reloading device of articles is provided to the vehicle body having wheels to run on the rails provided on the ceiling and also an air cleaning device is provided on the vehicle body side close to a wheel drive for preventing dusts generated on contact portions of the wheels from diffusing.
The conveying vehicle disclosed in the patent article 1 is installed in a hospital and configured that an air-cleaning device is provided on the vehicle body side close to the drive, that is, the configuration is just simple that an air around the drive is drawn by a fan and filtered.
A clean room for production of a semiconductor substrate, etc. is also provided with a conveying vehicle as explained above. When the conveying vehicle runs on the floor, rails are provided also on the floor and dusts arise at contact portions of the running wheels and accumulate on the rails. In such a clean room, there is a disadvantage that a sufficient cleanliness degree cannot be obtained just by introducing an air to a filter by a fan.